Mr. Philip Williams reports

ISOENERGY RELEASES 2025 SUSTAINABILITY REPORT DEMONSTRATING COMMITMENT TO RESPONSIBLE GROWTH

IsoEnergy Ltd. has released its sustainability report for the year ended Dec. 31, 2025. The report highlights the company's continued progress in integrating environmental stewardship, indigenous and community partnerships, work force development, and strong governance practices across its growing uranium portfolio in Canada, the United States and Australia. As IsoEnergy advances from exploration toward potential production and expands its operational footprint, the report demonstrates the company's commitment to responsible growth and long-term value creation. The full report is available on IsoEnergy's website.

Highlights:

• Environmental stewardship and operational excellence:
  • Recorded zero reportable environmental incidents across all projects;
  • Completed a two-year baseline water quality and hydrology program at the company's Larocque East project, providing critical environmental data to support future assessment, permitting and project advancement;
  • Continued environmental monitoring, mitigation, reclamation and restoration activities across exploration projects;
  • Enhanced water management infrastructure at the company's Tony M mine through the installation of remote monitoring systems, improving operational reliability and environmental oversight;
• Creating shared value through indigenous partnerships and community engagement:
  • Directed 46 per cent of the company's Canadian exploration spending to indigenous companies and contractors;
  • Achieved indigenous project site work force participation rates of 78 per cent in Quebec and 33 per cent in Saskatchewan;
  • Indigenous procurement represented 75 per cent of the company's exploration spend in Quebec and 42 per cent in Saskatchewan;
  • Supported the historic Starsailor rocket launch at the Matoush project in partnership with Space Concordia and the Cree Nation of Mistissini;
  • Invested in education, training and community initiatives, including high school tours at the Tony M mine, a mineral exploration scholarship with Northlands College, and sponsorship of community events in Saskatchewan and Quebec;
• Strengthening governance and organizational capacity:
  • Commenced trading on the NYSE American exchange, marking a significant milestone in the company's growth and commitment to enhanced governance, disclosure and accountability standards;
  • Expanded the leadership team through the appointment of a vice-president, strategy and commercial, and a director, external relations, supporting strategic growth, capital allocation, indigenous relations, stakeholder engagement and business execution;
  • Maintained a strong focus on cybersecurity, enterprise risk management, financial oversight and regulatory compliance across the organization.

Philip Williams, chief executive officer and director of IsoEnergy, commented: "As IsoEnergy continues to grow and advance a diversified portfolio of uranium projects across North America and Australia, maintaining high standards of environmental stewardship, community relationships and corporate governance remains fundamental to our success. During 2025, we strengthened our environmental programs, expanded partnerships with indigenous communities, increased local employment and procurement opportunities, and enhanced our leadership team and governance framework. The commencement of trading on the NYSE American marked an important milestone in our evolution, reflecting the scale of our ambitions and our commitment to transparency, accountability and operational excellence. As demand for secure, low-carbon nuclear energy continues to increase, we remain focused on advancing our projects responsibly and creating lasting value for rightsholders, communities, partners and shareholders."

About IsoEnergy Ltd.

IsoEnergy is a leading, globally diversified uranium company with substantial current and historical mineral resources in top uranium mining jurisdictions of Canada, the United States and Australia at varying stages of development, providing near-, medium- and long-term leverage to rising uranium prices. IsoEnergy is currently advancing its Larocque East project in Canada's Athabasca basin, which is home to the Hurricane deposit, boasting the world's highest-grade indicated uranium mineral resource.

IsoEnergy also holds a portfolio of permitted past-producing, conventional uranium and vanadium mines in Utah with a toll milling arrangement in place with Energy Fuels. These mines are currently on standby, ready for rapid restart as market conditions permit, positioning IsoEnergy as a near-term uranium producer.

We seek Safe Harbor.